FOR THE STRONG, A FAST, EXPENSIVE AND ENERGY-EFFICIENT NEW TRICYCLE

Want to have a shot at a world speed record under your own power? If you have $10,000 and a pair of reasonably strong thighs, the world's fastest bicycle—or is it a tricycle?—can be yours.

"It's the most efficient man-powered vehicle ever built," says Doug Unkrey, one of the designers of the Vector, a low-slung three-wheeler that set a single-rider-class world record at the May 3-4, 1980 Human Powered Speed Championships in Ontario, Calif. Propelled by David Grylls, it attained 56.64 mph through a 200-meter timing trap.

Now the Vector is the first fully streamlined racer available to the public. "We'll build one for anyone," says Unkrey, a partner in the Versatron Research Corporation of Anaheim, Calif., which made the Vector. A handmade Vector can even be ordered from Early Winters, a mail-order house at 110 Pre-fontaine Place South, Seattle, WA 98104.

What you'll get bears a minimal resemblance to an ordinary racing bike. The Vector, only 32 inches at its greatest height, has the tandem wheels forward, enclosed in a Fiberglas shell shaped something like the fuselage of a plane. The driver sits pretty much laid back, clearing the ground by about an inch, his legs set between the paired wheels as he works the pedals on the oversized, 100-tooth forward chainwheel that drives the single rear wheel. He steers with an airplane-type joystick, changes gears with a six-speed Shimano derailleur and watches his speed on a Pacer 2000 computerized speedometer. The 51-pound Vector is equipped with front internal drum brakes and a sturdy roll bar, because, says Unkrey, "on a 1% downgrade it'll quickly reach 70 mph." The manufacturer recommends, though, that it be operated in a velodrome, on a road-racing course or on any other smooth surface where car drivers won't interfere with it.

Last May, a two-man version of the Vector averaged 50.5 mph over the 42 miles from Stockton to Sacramento on Interstate 5. "Eventually, we may all commute on Vectors," says Unkrey.